Perceptible image quality defects, or non-uniformities, can be caused by variations within various components and/or subsystems in image printing systems. For example, a common image quality defect is that of banding. Banding generally refers to periodic defects on an image caused by a one-dimensional density variation in the process (slow scan) directions. An example of this kind of image quality defect, periodic banding, is illustrated in FIG. 1. FIG. 1 shows two periodic bands, band 1 and band 2, in an output print 3. Bands can result due to many different types of variations within components and/or subsystems, such as developer run out (variations in roll or drum diameter) in the developer roll or photoreceptor drum, wobble in the polygon mirror of the laser raster optical scanner (ROS), and the like.
While requiring tight tolerances for all components and/or subsystems, for example rotational components such as ROS rotating polygons and developer rolls, may reduce such perceptible image quality defects, tight tolerances often raise unit manufacturing costs and do not guarantee adequately uniform prints.